This invention relates to metal tubular scaffolds. More particularly it relates to adapting one type of such scaffolding to another type of such tubular scaffolding members.
Generally, in the past there have been two types of metal tubular scaffolding used. The first type is referred to in the trade as the "stack-up" type of scaffolding. This type is adapted for quick erection. However, it is limited in that is usually is built in pre-fabricated panels. These panels are not amenable to fitting through over-head steam lines and the like as the scaffold panels are stacked one atop the other to form a scaffold which must go above the steam line.
The second type of metal tubular scaffolding is known in the trade as the "tube lox" type. This tube lox scaffolding type is available from the Harsco Corporation, a corporation of Delaware. This tube lox type is not built in panels as are the stack-up type. Hence, the tube lox type of scaffolding is more versatile in assembling a scaffold in different configurations to fit around objects than the stack-up type. However, this tube lox type takes more time to assemble than does the stack-up type.
It would be advantageous to be able to transfer from one of these two types of metal tubular scaffolding to the other. Until the present, however, it has been the practice of those in the scaffolding industry to choose either one or the other of these two types of scaffolding for a particular scaffolding job, but not both types in the same scaffold. This has been done because the two different types of scaffolding employ different kinds of couplings to join the scaffold tubes in an end-to-end connective arrangement.
The coupling means which is employed normally by those in the trade using stack-up type scaffolding is one in which a removeable male coupling connector is fitted inside the ends of two tubes. This male connector is secured to both the tubes by a first removeable pin passing through holes in the first tube as well as through a hole in the part of the removeable male connector which is fitted inside the end of the first tube, and which is also connected by a second removeable pin which passes through holes in the second tube and a hole in that part of the removeable male connector which is fitted inside the second tube. This type of coupling means is illustrated in a scattered manner in the figures of the drawing. Therein a removeable male pin-type connector is denoted by reference numeral 18, a stack-up type scaffold tubing by reference numeral 12, a lower portion of a second stack-up type scaffold tubing by reference numeral 56, holes in the first tubing by reference numbers 34 and 36, holes in the second tubing by reference numbers 52 and 54, holes in the removeable pin-type male coupling connector 18 denoted by numbers 30, 32, a connecting pin by reference number 42, and a bolt serving as a connecting pin is denoted by reference number 38.
Note that there is not present in any one drawing two regular stack up type scaffolding tubes jointed end-to-end by a male coupling connector. This is because these drawings are illustrative of this invention in which there is either a transfer from stack up type scaffolding tubing to the tube lox type scaffolding, or a transfer from tube lox type scaffolding to stack-up type scaffolding as a scaffold is upwardly assembled.
The coupling means known for joining a first conventional tube lox scaffolding tube to a second one in an end-to-end fashion is a rotational type male in female coupling. This male-female rotational type coupling is also illustrated in the drawings. A particular type of rotational male coupling member is denoted by reference numeral 66 in FIGS. 1 and 5. A particular type of rotational female coupling means is denoted by reference numerals 80, 82, 84 and 88 in FIGS. 2, 4, and 5.
The pin-type coupling means has traditionally been used with prefabricated scaffold panels wherein several scaffolding tubes are permanently joined together into panels as illustrated by 106, 108, 110 in FIG. 7. On the other hand the rotational type coupling means has traditionally been used with non-prefabricated scaffolding tubes.
Since both scaffold tube types have their advantages and disadvantages; and since it has long been the convention in the scaffolding industry to choose either one type or the other, but not both, for any one scaffold assembly; and since there are occassions when it would be advantageous to use both scaffold tube types in a given scaffolding assembly; therefore, the present invention provides the scaffolding industry with such a scaffolding assembly, i.e. a hybrid of both scaffold tube types.